Physiological activity of various organs, such as the heart or brain, can be monitored, and this physiological activity can be analyzed to look for patterns that may assist in diagnosing various conditions. For example, the electrical activity of the heart can be monitored to track various aspects of the functioning of the heart. Cardiac electrical activity can be indicative of disease states or other physiological conditions ranging from benign to fatal. Cardiac monitoring devices can sense the cardiac electrical activity of a living being.